增加rpc下拉品类

src/Service/Interfaces/Product/ProductServiceInterface.php

@@ -455,4 +455,10 @@ interface ProductServiceInterface
      * @return mixed
      */
     public function getProductIsGroup(array $productLists);
+
+
+    /**
+     * 各级下拉品类
+     */
+    public function selectMultistageCategory();
 }